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Alkane biosynthesis by Aspergillus carbonarius ITEM 5010 through heterologous expression of Synechococcus elongatus acyl-ACP/CoA reductase and aldehyde deformylating oxygenase genes
No full textAbstract
In this study we describe the heterologous expression of the recently identified cyanobacterial pathway for long chain alkane biosynthesis, involving the reduction of fatty acyl-ACP to fatty aldehyde and the subsequent conversion of this into alkanes, in the filamentous fungus Aspergillus carbonarius ITEM 5010. Genes originating from Synechococcus elongatus strain PCC7942, encoding acyl-ACP/CoA reductase and aldehyde deformylating oxygenase enzymes, were successfully expressed in A. carbonarius , which lead to the production of pentadecane and heptadecane, alkanes that have not been previously produced by this fungus. Titers of 0.2, 0.5 and 2.7\ua0mg/l pentadecane and 0.8, 1.6 and 10.2\ua0mg/l heptadecane were achieved using glucose, Yeast malt and oatmeal media, respectively. Besides producing alkanes, we found elevated levels of internal free fatty acids and triglycerides in the alkane producing transformant. These findings can indicate that a yet unidentified, native fatty aldehyde dehydrogenase channels back the fatty aldehydes into the fatty acid metabolism, thus competing for substrate with the heterologously expressed fatty aldehyde deformylating oxygenase. These findings will potentially facilitate the future application of robust, fungal cell factories for the production of advanced biofuels from various substrates
Signal hole repair strategy based on sensor deployment density for mobile crowd network
No full textAbstract
In order to reduce the signal holes in wireless sensor networks, we proposed a sensor deployment density-aware signal hole repair strategy of mobile crowd network. On the one hand, based on the multi-dimensional connected graph, the density continuous jitter problem of the sensor network is solved effectively. Sensor density prediction method improves the efficiency of random deployment of sensor nodes. Based on the above schemes, the sensor deployment density sensing model is proposed. On the other hand, according to the regional geometry, diversity of the sensor network channel and density can detect the time domain channel impulse response signal successfully. Finally, the network signal is detected by the signal detection of the mobile crowd network. The signal holes can be detected and repaired based on coverage density and crowd. Experimental results show that the proposed algorithm has outstanding performance in terms of signal strength and signal void ratio compared with the energy-aware repair algorithm
On a semilinear mixed fractional heat equation driven by fractional Brownian sheet
No full textAbstract
In this paper, we consider the stochastic heat equation of the form
\u2202
u
\u2202
t
=
(
\u394
+
\u394
\u3b1
)
u
+
\u2202
f
\u2202
x
(
t
,
x
,
u
)
+
\u2202
2
W
\u2202
t
\u2202
x
,
where W is a fractional Brownian sheet,
\u394
+
\u394
\u3b1
is a pseudo differential operator on
R
which gives rise to a L\ue9vy process consisting of the sum of a Brownian motion and an independent symmetric \u3b1 -stable process, and
f
:
[
0
,
T
]
\ud7
R
\ud7
R
\u2192
R
is a nonlinear measurable function. We introduce the existence, uniqueness, H\uf6lder regularity and density estimate of the solution.
MSC: 60G22, 60H07, 60H15
Antiviral activity of animal venom peptides and related compounds
No full textAbstract
Viruses exhibit rapid mutational capacity to trick and infect host cells, sometimes assisted through virus-coded peptides that counteract host cellular immune defense. Although a large number of compounds have been identified as inhibiting various viral infections and disease progression, it is urgent to achieve the discovery of more effective agents. Furthermore, proportionally to the great variety of diseases caused by viruses, very few viral vaccines are available, and not all are efficient. Thus, new antiviral substances obtained from natural products have been prospected, including those derived from venomous animals. Venoms are complex mixtures of hundreds of molecules, mostly peptides, that present a large array of biological activities and evolved to putatively target the biochemical machinery of different pathogens or host cellular structures. In addition, non-venomous compounds, such as some body fluids of invertebrate organisms, exhibit antiviral activity. This review provides a panorama of peptides described from animal venoms that present antiviral activity, thereby reinforcing them as important tools for the development of new therapeutic drugs
Microcystic adnexal carcinoma (MAC)-like squamous cell carcinoma as a differential diagnosis to Bell\ub4s palsy: review of guidelines for refractory facial nerve palsy
No full textAbstract
Background
Bell\ub4s palsy is the most common cause of facial paralysis worldwide and the most common disorder of the cranial nerves. It is a diagnosis of exclusion, accounting for 60\u201375% of all acquired peripheral facial nerve palsies. Our case shows the first case of a microcystic adnexal carcinoma-like squamous cell carcinoma as a cause of facial nerve palsy.
Case presentation
The patient, a 70-year-old Caucasian male, experienced subsequent functional impairment of the trigeminal and the glossopharyngeal nerve about 1\ubd\u2009years after refractory facial nerve palsy.
An extensive clinical work-up and tissue biopsy of the surrounding parotid gland tissue was not able to determine the cause of the paralysis. Primary infiltration of the facial nerve with subsequent spreading to the trigeminal and glossopharyngeal nerve via neuroanastomoses was suspected. After discussing options with the patient, the main stem of the facial nerve was resected to ascertain the diagnosis of MAC-like squamous cell carcinoma, and radiochemotherapy was subsequently started.
Conclusion
This case report shows that even rare neoplastic etiologies should be considered as a cause of refractory facial nerve palsy and that it is necessary to perform an extended diagnostic work-up to ascertain the diagnosis. This includes high-resolution MRI imaging and, as perilesional parotid biopsies might be inadequate for rare cases like ours, consideration of a direct nerve biopsy to establish the right diagnosis
Accuracy of 177 Lu activity quantification in SPECT imaging: a phantom study
No full textAbstract
Background
The aim of the study is to assess accuracy of activity quantification of
177
Lu studies performed according to recommendations provided by the committee on Medical Internal Radiation Dose (MIRD) pamphlets 23 and 26. The performances of two scatter correction and three segmentation methods were compared. Additionally, the accuracy of tomographic and planar methods for determination of the camera normalization factor (CNF) was evaluated.
Eight phantoms containing inserts of different sizes and shapes placed in air, water, and radioactive background were scanned using a Siemens SymbiaT SPECT/CT camera. Planar and tomographic scans with
177
Lu sources were used to measure CNF. Images were reconstructed with our SPEQToR software using resolution recovery, attenuation, and two scatter correction methods (analytical photon distribution interpolated (APDI) and triple energy window (TEW)). Segmentation was performed using a fixed threshold method for both air and cold water scans. For hot water experiments three segmentation methods were compared as folows: a 40% fixed threshold, segmentation based on CT images, and our iterative adaptive dual thresholding (IADT). Quantification error, defined as the percent difference between experimental and true activities, was evaluated.
Results
Quantification error for scans in air was better for TEW scatter correction (<6%) than for APDI (<11%). This trend was reversed for scans in water (<10% for APDI and <14% for TEW). For hot water, the best results (<18% for small objects and <5% for objects >100\ua0ml) were obtained when APDI and IADT were used for scatter correction and segmentation, respectively. Additionally, we showed that planar acquisitions with scatter correction and tomographic scans provide similar CNF values. This is an important finding because planar acquisitions are easier to perform than tomographic scans. TEW and APDI resulted in similar quantification errors with APDI showing a small advantage for objects placed in medium with non-uniform density.
Conclusions
Following the MIRD recommendations for data acquisition and reconstruction resulted in accurate activity quantification (errors <5% for large objects). However, techniques for better organ/tumor segmentation must still be developed
Challenges newly-arrived migrant women in Montreal face when needing maternity care: Health care professionals\u2019 perspectives
No full textAbstract
Background
People who leave their country of origin, or the country of habitual residence, to establish themselves permanently in another country are usually referred to as migrants. Over half of all births in Montreal, Canada are to migrant women. To understand healthcare professionals\u2019 attitudes towards migrants that could influence their delivery of care, our objective was to explore their perspectives of challenges newly-arrived migrant women from non-Western countries face when needing maternity care.
Method
In this qualitative multiple case study, we conducted face-to-face interviews with 63 health care professionals from four teaching hospitals in Montreal, known for providing maternity care to a high volume of migrant women. Interviews were transcribed and thematically analysed.
Results
Physicians, nurses, social workers, and therapists participated; 90% were female; and 17% were themselves migrants from non-Western countries. According to participants, newly-arrived migrant women face challenges at two levels: (a) direct care (e.g., understanding Canadian health care professionals\u2019 expectations, communicating effectively with health care professionals), and (b) organizational (e.g., access to appropriate health care). Challenges women face are strongly influenced by the migrant woman\u2019s background as well as social position (e.g., general education, health literacy, socio-cultural integration) and by how health care professionals balance women\u2019s needs with perceived requirement to adhere to standard procedures and regulations.
Conclusions
Health care professionals across institutions agreed that maternity care-related challenges faced by newly-arrived migrant women often are complex in that they are simultaneously driven by conflicting values: those based on migrant women\u2019s sociocultural backgrounds versus those related to the implementation of Canadian guidelines for maternity care in which consideration of migrant women\u2019s particular needs are not priority
Drug-induced Parkinson\u2019s disease modulates protein kinase A and Olfactory Marker Protein in the mouse olfactory bulb
No full textAbstract
Background
Olfaction is often affected in parkinsonian patients, but dopaminergic cells in the olfactory bulb are not affected by some Parkinson-inducing drugs. We investigated whether the drug MPTP produces the olfactory deficits typical of Parkinson and affects the olfactory bulb in mice.
Findings
Lesioned and control mice were tested for olfactory search, for motor and exploratory behavior. Brains and olfactory mucosa were investigated via immunohistochemistry for thyrosine hydroxylase, Olfactory Marker Protein and cyclic AMP-dependent protein kinase as an intracellular pathway involved in dopaminergic neurotransmission. MPTP induced motor impairment, but no deficit in olfactory search. Thyrosine hydroxylase did not differ in olfactory bulb, while a strong decrease was detected in substantia nigra and tegmentum of MPTP mice. Olfactory Marker Protein decreased in the olfactory bulb of MPTP mice, while a cyclic AMP-dependent protein kinase increased in the inner granular layer of MPTP mice.
Conclusions
MPTP mice do not present behavioural deficits in olfactory search, yet immunoreactivity reveals modifications in the olfactory bulb, and suggests changes in intracellular signal processing, possibly linked to neuron survival after MPTP
ADAR1 overexpression is associated with cervical cancer progression and angiogenesis
No full textAbstract
Background
This study aimed to assess the role of RNA-dependent adenosine deaminase (ADAR1) in cervical squamous cell carcinoma occurrence and progression.
Methods
ADAR1 expression levels in stage IA and stage IIA cervical squamous cell carcinoma (group A), cervical intraepithelial neoplasia (CIN) specimens (group B), as well as normal and inflamed cervical tissue samples (group C) were assessed by immunohistochemistry. Clinical and pathological data of cervical squamous cell carcinoma patients undergoing surgery were retrospectively evaluated. Chi-square test, comparative analysis of survival curve, disease-free survival and COX risk assessment method were used to understand the association of ADAR1 with the occurrence and progression and prognostic significance of cervical squamous cell carcinoma.
Results
ADAR1 is expressed in the cytoplasm and nuclei. The expression level was high in squamous cell carcinoma tissues (81.18%), while relatively low in the CIN group (21.56%). And there was no expression in non-cancerous tissues. The differences between them were statistically significant using P \u2009<\u20090.05 as criterion. One-factor analysis revealed that ADAR1 was significantly correlated with tumor diameter, horizontal diffusion diameter, vascular invasion, parametrial invasion, vaginal involvement, and pathologically diagnostic criteria for perineural invasion (PNI). Meanwhile, the overall survival rate of ADAR1 positive patients was significantly lower compared with that of patients with no ADAR1 expression ( P \u2009<\u20090.05). Analysis also showed that disease-free survival time of ADAR1 positive patients was shorter than that of ADAR1 negative patients, and the difference was significant ( P \u2009<\u20090.01). Finally, COX risk assessment showed that parametrical invasion had independent prognostic factors for overall survival of squamous cell carcinoma.
Conclusions
Results indicated that ADAR1 might play an important role in the occurrence, progression and prognosis of cervical squamous cancer
